Horizontally axised evaporator of the rotary wiped thin film type



y 1966 A. R. GUDHEIM 3,253,543

HORIZONTALLY AXISED EVAPORATOR OF THE ROTARY WIPED THIN FILM TYPE Filed March 18, less INVENTOR.

United States Patent 1ce 3,253,643 HORIZONTALLY AXISED EVAPORATOR OF THE ROTARY WIPED THIN FILM TYPE Arne R. Gudheim,'N. Main St., Peter-sham, Mass. Filed Mar. 18, 1963, Ser. No. 265,994 4 Claims. (Cl. 159-6) This invention relates in general to an improvement with regard to the horizontal reverse taper thin film processing machine shown in my prior Patent 2,927,634 dated March 8, 1960,

In the prior art in horizontal thin film processing machinery, the vapors generated during the operation flow in the same direction as the product, that is, concurrent with respect to the material, e.g. liquid being processed from the feed-in area to the product or bottoms-out point. For many operations, this is entirely satisfactory but there are situations in which it has been found that it is preferable for processing reasons for the vapor to flow in the opposite direction, that is, counter to the flow of the material under process. Ordinarily in such cases there tends to be considerable entrainment of the liquid with the vapor which of course is an undesirable condition. The present invention has for its principal object the provision of a satisfactory apparatus in which the vapor is forced out at a point adjacent the feed-in of the material to be processed, i.e., at the remote end of the machine from the product or bottoms-out position; and the provision of such apparatus wherein the vapor outlet is located longitudinally outwardly in the chamber with respect to the in-feed point and at the opposite side of the in-feed point from the bottoms-out point, and this arrangement has been found to be satisfactory with respect to the problem of entrainment of fluid with the vapor.

It is another object of the present invention to provide means on the rotor for aiding in the progress of fluids of high viscosity which are ordinarily not possible to be processed at desired conditions; and the provision of such means comprising elements referred to hereinafter as pushers located near the end of the process section and mounted on the rotor blades for pushing the stock along as it tends to become stiffer and stiffer and so resists the progress to the bottoms-out or product collection point.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings, in which FIG. 1 is a longitudinal section through a reverse taper machine according to the present invention;

FIG. 2 is a section of the rotor on an enlarged scale taken on line 22 of FIG. 1 and showing the positioning of the pusher blades, and

FIG. 3 is a view similar to FIG. 1 illustrating a machine embodying forward taper according to the present invention.

In carrying out the present invention, any kind of supporting arrangement or framework can be used for the apparatus and only so much is illustrated as to explain the invention. In particular, end supporting plates or closing heads 26 and 12 are supported in fixed position and they mount thereon a rotary tube or pipe-like member 14 which extends at one end of the machine as at 16 and is driven by any kind of motor which may be found to be convenient or desirable.

The end plates and 12 also mount between them the casing of the machine indicated at 18 and on which a temperature regulating jacket 20 is mounted. This jacket may accept steam, hot water, cooling water, etc. as conditions may require.

The end plate 10 mounts a vapor collecting chamber 22 which may be of any desired description but it is in 3,253,643 Patented May 31, 1966 general closed and the vapor escapes through the open connection 24, it being understood that this vapor is occasioned by the action of the machine in processing ma terial therein and also it is to be understood that various kinds of conventional bearings, etc. can be utilized for the proper mounting of the pipe or tube 14 in end plate 12 and in the extreme end plate 26 mounted on the walls of chamber 22.

Mounted on the tube 14 are a series of generally radial vanes or blades generally indicated at 28. These vanes are substantially alike and taper from end-mend in conformance with the inner wall of the chamber 18, with their outer edges positioned in closely spaced relation with respect to said inner wall of the chamber. The material to be processed is fed into the connection 30 and the bottoms or finished product is drained or extracted by connection 32 at the opposite end of the chamber. Also any kind of fan arrangement or vapor entrainment means can be utilized in the chamber 22 as may be found desirable.

The vanes or blades 28 are recessed or cut out as at 31 from the edges thereof adjacent 22 inwardly. These cut-outs accommodate a cylindrical projection 33 which is horizontal, open at both ends, and mounted as on an annular transverse wall or diaphragm 35 peripherally secured to wall 10. The projection extends in a direction toward the product outlet from chamber 22. The vapor produced by the action of the machine escapes without any appreciable entrainment of the fluid being processed, and this is due principally to the novel darn arrangement as formed by the cut-out portions of the vanes 28 and the cylindrical projection 33, as well as the wall 10, the latter extending annularly from the cylindrical projection to the adjacent wall of the chamber.

Under certain conditions of heavy viscosity as for instance 50,000 centipoises at 400 F., the machine operates perfectly satisfactorily but over thatamount there is trouble with the stiffening material that is being processed. It tends to stick to the side walls of the chamber short of the bottoms-out connection at 32. For instance, if the temperature were to be lowered fifty degrees from 400 F. to 350 F., the viscosity of certain materials would probably be increased two to threefold, causing sticking in the chamber.

This is avoided in the present case by the use of pusher elements generally indicated at 34, 34, these being arcshaped blades which are connected to the tips of the vanes and are in slight angular relationship with respect to a diameter of the pipe 14 so that the blades actually form portions of worms and act to push the stiffened material along to its bottoms-out location. These pushers are ordinarily provided adjacent the bottoms-out portion of the devices as of course this is the point where the material has the highest viscosity due to the processing through the machine.

Referring now to FIG. 3 there is shown the reverse operation with respect to the reverse taper machine shown in FIG. 1. In this case the construction is the same except that the taper of the machine is in a divergent relationship or on an enlarged relationship with respect to the chamber from the feed-in to the bottoms-out point; but in any event the vapor arrangement exit is adjacent the infeed position as before. In FIG. 3 the central pipe or tube is indicated at 44, the vapor chamber at 46, the vanes at 48, 48, and the bottoms-out connection whereas the feed-in connection is indicated at 52. Other- 'wise however the invention is the same as before.

The same dam arrangement is also effective in this type of machine, the cylindrical projection 54 being located at the small end, next to the chamber 46 but still extending toward the product outlet as before.

The novel dam arrangement has been found to be effective also in cases where the machine is placed vertically whether the machine is tapered or straight and cylindrical, and it will be appreciated that vapor entrainment with the fluid being processed is substantially eliminated because the vapor is directed to the central part of the casing 18 whereas the blades cause the input material to be at once spun out to the inner surface of the wall of the casing.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. Apparatus of the class described comprising a horizontal chamber of generally conical formation, a temperature control jacket about the chamber exteriorly thereof, a horizontal rotor in the chamber, means to rotate the rotor, generally radially and axially arranged vanes on the rotor extending from the axis into close association with the interior wall of the chamber leaving a small space between the peripheral tips of the vanes and the said interior wall,

a closing head and concentrate outlet at one end of the chamber, a feed inlet and a vaporoutlet at the other end of the chamber with the vapor outlet positioned axially beyond the feed inlet, an annular transverse diaphragm between the vapor outlet and feed inlet, said diaphragm being mounted at its periphery on the wall of the chamber,.

a generally cylindrical projection on the diaphram surrounding the open center portion thereof and extending toward the concentrate end of the chamber, said projection being open at both ends and forming with the diaphragm a dam between the feed inlet and the vapor outlet wherein the dam is centrally open and provides communication from the chamber to the vapor outlet, the end portions of the vanes adjacent the feed inlet extending into close association with the projection.

2. The apparatus recited in claim 1 including cutout areas in the vanes accommodating the projection so that portions of the vanes rotate about the projection.

3. The apparatus recited in claim 1 including cutout areas in the vanes accommodating the p-rojection so that portions of the vanes rotate about the projection both inside and outside thereof.

4. Apparatus of the class described comprising a wall forming a chamber having an interior of the general shape of a horizontal come, a temperature control jacket about the wall, a horizontal rotor in the chamber, means to rotate the rotor, generally radially and axially arranged vanes on the rotor extending into close association with the interior of the Wall leaving a small generally uniform space between the peripheral tips of the vane-s and the said wall, an inlet in said chamber for the material to be concentrated and a concentrate outlet in said chamber at a spa-ced point therefrom, to discharge concentrate moving along the wall, and means on said vanes for mechanically pushing the material being processed toward the concentrate outlet, said means comprising arc-shaped members attached to and extending between pairs of vanes adjacent said tips and in close association with respect to the interior Wall of the chamber, said members each having edge portions thereof spaced from the wall of the chamber substantially the distance from the vane tips to said wall, said members being located adjacent the concentrate outlet, to force the concentrate toward the outlet.

References Cited by the Examiner UNITED STATES PATENTS 1,420,648 6/1922 Mabee 159-6 2,068,091 1/1937 Stoltz 196-71 2,656,885 10/1953 Hughes 159-11 2,740,580 4/1956 Schr'niedel 233-7 2,766,193 10/ 1956 Schneider 202-236 2,774,415 12/ 1956 Belcher 159-6 2,927,634 3/1960 Gudheim '159-6 2,993,842 7/1961 Smith 159-6 X 3,020,211 2/1962 Smith 159-6 X 3,067,812 12/1962 Latinen et al. 159-6 FOREIGN PATENTS 1,123,231 9/1956 France. 586,865 4/ 1958 Italy.

NORMAN YUDKOFF, Primary Examiner. 

1. APPARATUS OF THE CLASS DESCRIBED COMPRISING A HORIZONTAL CHAMBER OF GENERALLY CONCIAL FORMATION, A TEMPERATURE CONTROL JACKET ABOUT THE CHAMBER EXTERIORLY THEREOF, A HORIZONTAL ROTOR IN THE CHAMBER, MEANS TO ROTATE THE ROTOR, GENERALLY RADIALLY AND AXIALLY ARRANGED VANES ON THE ROTOR EXTENDING FROM THE AXIS INTO CLOSE ASSOCIATION WITH THE INTERIOR WALL OF THE CHAMBER LEAVING A SMALL SPACE BETWEEN THE PERIPHERAL TIPS OF THE VANES AND THE SAID INTERIOR WALL, A CLOSING HEAD CONCENTRATE OUTLET AT ONE END OF THE CHAMBER, A FEED INLET AND A VAPOR OUTLET AT THE OTHER END OF THE CHAMBER WITH THE VAPOR OUTLET POSITIONED AXIALLY BEYOND THE FEED INLET, AN ANNULAR TRANSVERSE DIAPHRAGM BETWEEN THE VAPOR OUTLET AND FEED INLET, SAID DIAPHRAGM BEING MOUNTED AT ITS PERIPHERY ON THE WALL OF THE CHAMBER, A GENERALLY CYLINDRICAL PROJECTION ON THE DIAPHRAM SURROUNDING THE OPEN CENTER PORTION THEREOF AND EXTENDING TOWARD THE CONCENTRATE END OF THE CHAMBER, SAID PROJECTION BEING OPEN AT BOTH ENDS AND FORMING WITH THE DIAPHRAGM A DAM BETWEEN THE FEED INLET AND THE VAPOR OUTLET WHEREIN THE DAM IS CENTRALLY OPEN AND PROVIDES COMMUNICATION FROM THE CHAMBER TO THE VAPOR OUTLET, THE END PORTIONS OF THE VANES ADJACENT THE FEED INLET EXTENDING INTO CLOSE ASSOCIATION WITH THE PROJECTION 